Mass and Weight · Unit Converter

Convert Milligram to Troy Ounce

Convert milligrams to troy ounces instantly. 1 milligram = 3.215075e-5 troy ounce — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Troy Ounce to Milligram converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Dr. Ashok Kumar K, Ph.D.
Mass and Weight category 2 min read Published Last reviewed Updated

Units explained

Metric / SI

Milligram

What is a milligram?

A milligram (mg) equals one-millionth of a kilogram, or 0.001 gram.

Origin of the milligram

From the SI prefix 'milli-' (from Latin 'mille', thousand).

Where it is used

Standard for medicine dosing, nutrition labels, and fine jewelry.

When and where it was developed

Part of the original metric system of 1795.

Troy & Apothecary

Troy Ounce

What is a troy ounce?

The troy ounce (ozt) equals about 31.103 grams, one-twelfth of a troy pound.

Origin of the troy ounce

From the Troy system of weights associated with Troyes, France.

Where it is used

The global standard for pricing gold, silver, platinum, and palladium.

When and where it was developed

Established in the medieval Troy system and retained for precious metals.

Milligram to Troy Ounce conversion formula

The relationship between milligrams and troy ounces:

1 mg = 3.215075e-5 oz t
1 oz t = 31103.4768 mg

To convert milligrams to troy ounces, multiply the value in milligrams by 3.215075e-5. To reverse, multiply troy ounces by 31103.4768.

How to use this converter

Type a value into the calculator. The result in troy ounces updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Troy Ounce to Milligram converter for the reverse direction.

Step-by-step: convert milligrams to troy ounces

  1. Write down the value in milligrams (mg).
  2. Multiply that value by the factor 3.215075e-5.
  3. The product is the equivalent value in troy ounces (oz t).
  4. To reverse, multiply the troy ounce value by 31103.4768.

Worked examples

Example 1 — Convert 1 mg to oz t:
1 × 3.215075e-5 = 3.215075e-5 oz t

Example 2 — Convert 100 mg to oz t:
100 × 3.215075e-5 = 0.0032150747 oz t

Real-world example — Packaging gauge

A 4-milligram plastic bag thickness is a common spec for grocery and freezer bags. Converting from milligrams to troy ounces is what packaging buyers do whenever they bridge US and metric supplier quotes.

4 mg × 3.215075e-5 = 0.000128603 oz t

Real-world example — Plastic film and laminate thickness

A 500-milligram sheet is a typical spec for ID-card laminates and film overlays. Converting to troy ounces aligns the value with the unit most CAD systems and material datasheets prefer.

500 mg × 3.215075e-5 = 0.0160753733 oz t

Milligram to Troy Ounce conversion table

Standard reference values for converting milligrams to troy ounces:

Milligram [mg]Troy Ounce [oz t]
0.013.215075e-7
0.13.215075e-6
13.215075e-5
26.430149e-5
39.645224e-5
40.000128603
50.0001607537
100.0003215075
200.0006430149
300.0009645224
400.0012860299
500.0016075373
1000.0032150747
5000.0160753733
10000.0321507466

Frequently asked questions

How many troy ounces is 1 milligram?
1 milligram equals 3.215075e-5 troy ounce.
How do I convert milligrams to troy ounces?
Multiply the value in milligrams by 3.215075e-5 to get troy ounces.
How do I convert troy ounces back to milligrams?
Multiply the value in troy ounces by 31103.4768, or use the Troy Ounce to Milligram converter.
How many troy ounces is 100 milligrams?
100 milligrams equals 0.0032150747 troy ounces, because 100 × 3.215075e-5 = 0.0032150747.

Convert Milligram to other weight units

Show all Milligram conversions
Metric / SI (17 units)
Avoirdupois (15 units)
Troy & Apothecary (10 units)
Indian / South Asian (6 units)
Scientific / Atomic (9 units)
Astronomical (4 units)
Biblical / Ancient (14 units)
Force / Engineering (5 units)

Sources & references

Conversion factor (1 mg = 3.215075e-5 oz t) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.